Effects of Y2O3 doping on phase structure and thermal physical properties of La2Zr2O7 ceramics

被引：0
作者：
Xie M. [1 ,2 ]
Zhang Y. [2 ]
Zhou F. [2 ]
Song X. [2 ]
An S. [1 ,2 ]
机构：
[1] School of Metallurgy Ecological Engineering, University of Science and Technology Beijing, Beijing
[2] School of Materials and Metallurgy, Inner Mongolia University of Science and Technology, Baotou, 014010, Inner Mongolia
来源：
Kuei Suan Jen Hsueh Pao/Journal of the Chinese Ceramic Society | 2016年 / 44卷 / 09期
关键词：
Doped Lanthanum zirconate; Pyrochlore; Thermal barrier coating materials; Thermal properties;
D O I：
10.14062/j.issn.0454-5648.2016.09.16
中图分类号：
学科分类号：
摘要：
(La1-xYx)2Zr2O7 (x=0, 0.1, 0.2) ceramics were synthesized by Y2O3 doping in La2Zr2O7. The phase structure was analysed by X-ray diffractometer. The feature surface was determined by scanning electron microscope. The thermal diffusivities and thermal expansion coefficient (TEC) of the ceramic materials were examined by a laser-flash method and thermal dilatometer, respectively. The results show that (La1-xYx)2Zr2O7 exhibits a pyrochlore crystal structure, a dense microstucture and a superior structural stability at a high temperature. The ceramic doped with smaller Y3+ shows a higher thermal expansion coefficent(TEC) (x=0.2), lower thermal diffusivities and a nearly temperature-independent behavior reported as glass-like extraordinarily low thermal conductivities. The thermal conductivity of La1.6Y0.4Zr2O7 is 1.28 W/(m·K) at 1 000℃, and the average TEC is 9.7×10-6/K. © 2016, Editorial Department of Journal of the Chinese Ceramic Society. All right reserved.
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页码：1352 / 1356
页数：4
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